Hybridization and polyploidy shaped the evolutionary history of a complex of cryptic species in European woodrushes (Luzula sect. Luzula)

Polyploidization has played a central role in the evolutionary history of most plant lineages, yet it poses significant challenges for phylogenetic inference, particularly in allopolyploid complexes with reticulate species relationships. Luzula sect. Luzula (Juncaceae) is a taxonomically intricate group characterized by widespread polyploidy, agmatoploidy, and high morphological uniformity. Focusing on the Eastern Alps, a key center of its diversity, we collected 1,002 samples of nine species and applied an integrative framework combining ddRADseq, plastid sequencing, relative genome size estimation, and chromosome counting to disentangle its evolutionary history. We extended previously inferred phylogenetic relationships and assessed gene flow among diploids, establishing a baseline for investigating the origin of polyploids. By analyzing patterns of genotype frequencies and genetic affinities to diploids, we inferred the most likely parental species of polyploids and identified key hybridization events shaping the current taxonomic and karyotypic diversity within this group. Our results reveal weak genetic differentiation among some diploid lineages, likely reflecting gene flow and incomplete lineage sorting. We propose a common allopolyploid origin of two tetraploids, which subsequently gave rise to a third tetraploid and a hexaploid species through interploidy hybridization. Although the parental species of some polyploids remain obscure, our genomic data highlight polyploidy and hybridization as major drivers of speciation in this poorly understood lineage. This study underscores the value of integrative approaches in resolving reticulate plant phylogenies and advances our understanding of polyploid speciatio

Alcoholic extracts of Russian sage (Salvia yangii) contain bioactive terpenoids with inhibitory activity against grapevine downy mildew (Plasmopara viticola)

Background: Plant extracts are promising eco-friendly alternatives to synthetic fungicides for developing sustainable plant protection strategies. Grapevine downy mildew, caused by Plasmopara viticola, is a devastating disease that requires frequent fungicide applications, making it an ideal target for plant-based products. Salvia officinalis extracts are known to reduce downy mildew severity, but little is known about the efficacy and chemical composition of other fast-growing Salvia species with low economic value. This study aimed to evaluate the efficacy of alcoholic extracts of Russian sage (Salvia yangii) against grapevine downy mildew and to annotate bioactive compounds against P. viticola. Results: Alcoholic extracts from flowers, leaves, and shoots of Russian sage decreased downy mildew severity on grapevine leaf disks. In particular, leaf and flower extracts showed efficacy comparable to that of copper-based fungicides, whereas stem extract was only partially active. Shoot extracts were fractionated by preparative liquid chromatography (LC), and the activity of the resulting fractions was assessed against P. viticola using leaf disk assays. Untargeted metabolomic analyses revealed putative terpenoids as the main components of the active fractions, as determined by gas chromatography-mass spectrometry (GC-MS) and ultra-high-pressure liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) analyses. Specifically, 7-methylrosmanol, 12-O-methylcarnosic acid, carnosic acid, and carnosol were identified as the main bioactive compounds against P. viticola. Conclusion: Russian sage represents a valuable source of bioactive compounds for sustainable plant protectio

Linking microbial function and remote sensing for understanding drylands

Drylands, covering over 40% of Earth's land surface, are expanding due to accelerating aridification and vegetation loss. Their microbial communities sustain essential processes such as carbon fixation, nitrogen cycling, and trace gas regulation; yet they remain largely invisible to global models. While microbiome studies reveal mechanistic details at local scales, environmental monitoring requires spatial continuity. We argue that advances in remote sensing, with its increasing resolutions, now allow microbial processes to be observed, scaled, and modeled across regions. Linking omics and spectral data can reveal microbial 'sentinels' of ecosystem change, transforming microbial ecology into a spatially predictive science. This integration provides a foundation for early-warning systems of biodiversity loss and land degradation, positioning microbes as measurable actors in Earth system dynamic

Decoding microbial volatile signals in host–microbiome crosstalk

The human gut microbiome is a complex microbial ecosystem which has a profound impact on host health and disease. The research focus in this area is rapidly moving from taxonomy to functionality, elucidating the biological role of small molecules produced by the gut microbiome in regulating host metabolism. Among these, microbial volatile organic compounds (mVOCs) play several roles in bacterial communication and microbe-host signaling. Volatilomics, the comprehensive study of volatile metabolites, is emerging as a powerful tool for discovering and investigating these interactions. In this review we examine the current understanding of mVOCs in the gut and highlight how dedicated in vitro and ex vivo volatilomics experiments, alongside in vivo studies, can uncover the biological roles for these emerging small molecule

Effect of tree microenvironment on sweet cherry fruit transpiration, xylem, and phloem flows

This study provides an overview of how shading covers can affect air vapor pressure deficit (VPD) and sweet cherry water status, and it fruit absolute growth rate (AGR), and its xylem (X), phloem (P), and transpiration (T) flows. The experiment was carried out from April to June 2024 on a 14-year-old sweet cherry orchard, variety ‘Sweet Saretta’ grafted on ‘Gisela 6’. These trees were cultivated under: (i) direct sunlight conditions, and (ii) a 20 % shading black net. During the experiment, environmental conditions, such as air temperature (Ta) and relative humidity (RH), were monitored, and from this data the VPD was calculated. Tree water status was assessed by measuring at 9:00 h stomatal conductance (gs), and net photosynthesis (Pn) and at 12:00 h stem water potential (Ψstem). During the experiment, the fruit equatorial diameter was measured at regular time intervals during the season. At the same time, fruit daily diameter variations were monitored precisely every 30 min at 33, 38, and 43 days after full bloom, corresponding with the early and late stage II, and with the early stage III of fruit growth. From these data, the 30-minute fruit AGR, X, P, and T flows were estimated, and their daily contribution was calculated. In addition, fruit X, P, and T flows were correlated with VPD at different fruit growth stages. During the experiment, VPD was reduced on average by 19 % under the net. At the same time, trees cultivated under a net showed less negative values of Ψstem and higher values of gs and Pn. Differences between treatments were also observed in the 30-minute and daily contributions of fruit AGR, X, P, and T flows. Results showed that cropping condition slightly affected the relationship between VPD and fruit T, X, and P flow. In conclusion, under netting, the lower air VPD had some positive effects on tree water status and seasonal fruit growth. These conditions mainly minimized the daily contribution of fruit T, X, and P flows, except in the case of P flow at stage III, and did not significantly affect the correlation between these flows and the VPD

Contrasting diversification patterns across wood rushes from Luzula sect. Luzula (Juncaceae) revealed by 3RAD genome-wide sequencing

Among the different mechanisms triggering diversification processes, chromosomal rearrangements that generate karyotypic changes are common in plants. Luzula (Juncaceae) is among the few angiosperm genera with holocentric chromosomes, which can undergo chromosome fission (agmatoploidy) or fusion (symploidy), resulting in karyotypes with different chromosome numbers and sizes. In this study, 3RAD genome-wide sequencing data and plastid sequences were used to explore evolutionary trends and patterns of genetic diversification among diploid taxa of Luzula sect. Luzula centred in the European Alpine System. In addition, we inferred its phylogenetic relationships to other closely related sections, of which several proved to be non-monophyletic. The species of Luzula sect. Luzula are segregated into three lineages, which show contrasting patterns regarding bifurcated branching, reticulation, and levels of coancestry as a result of different evolutionary histories. Agmatoploid species are found in two of these clades, displaying different karyotypes, while the third lineage comprises only L. campestris. Based on a molecular dating reconstruction, at least two putatively independent transitions towards agmatoploidy are estimated, which have occurred between the mid- and late Pleistocene in Luzula sect. Luzula. In addition, several trans-continental migrations, e.g. between Europe and Africa, were inferred. This study provides a new perspective on the complexity of diversification among wood rushes, which may serve as a basis for future exploration of the occurrence of agmatoploidy and its role in species diversificatio

Varietal volatile patterns in young and model-aged white wines: a case study on eighteen monovarietal Italian wine types

During aging, wines undergo substantial compositional transformation through complex reactions impacting wine volatile composition. Most white wines are obtained from aromatically neutral grape varieties, although aging might induce chemical changes of potential relevance for viticulture and enology. This study investigated aging-induced changes in varietal volatile compounds across 18 monovarietal white wine types from nine Italian regions, namely Albana, Cortese, Arneis, Erbaluce, Falanghina, Fiano, Garganega, Gewürztraminer, Greco di Tufo, Lugana, Müller-Thurgau, Nosiola, Pallagrello bianco, Pinot grigio, Ribolla gialla, Verdicchio, Vermentino, and Vernaccia. Results provided for the first time clear chemical clues about the existence of distinct aging patterns for each wine type. Aging treatment enhanced classification complexity while simultaneously reducing intra-varietal diversity. Certain wines developed characteristic patterns and markers during aging. In particular, compounds such as methyl salicylate, cineole isomers, dimethyl sulfide (DMS) and methanethiol were primarily associated with specific varietal types. These findings provide insights for optimizing viticultural and winemaking strategies to manage varietal typicality during agin

The role of mycobiome in terroir and during Muscat grapes fermentation unveiled by multi-omic analysis

The wine microbiome is a key determinant in shaping wine terroir. To date, a comprehensive understanding of how microbial signatures influence wine metabolic profile remains poorly understood. To address this, in the present study an integrated shotgun metagenomics and untargeted metabolomic approach was employed to investigate the wine metabolome and connect the composition and functions of microbiomes involved in wine fermentation of Muscat grapes harvested in Italy and Greece. Beta diversity highlighted the dissimilarity between Italian and Greek fungal terroirs. A marked reduction in diversity during fermentation underscored the dominance of the inoculated Saccharomyces cerevisiae starter culture. The LEfSe analysis revealed an enrichment of Torulaspora delbrueckii in Greek samples, while Kluyveromyces marxianus and lactis were more abundant in Italian samples. Functional analysis revealed geographic differences in nucleotide, fatty acids and lysine metabolisms. Significant shifts were observed in energy, carbohydrate, and amino acid metabolisms, reflecting terroir-specific microbial activity. The metabolomics data highlighted regional differences in oligosaccharides, glycosylated phenolics, peptide and amino acid turnover, and central redox metabolites, suggesting divergent microbial responses and metabolic trajectories shaped by terroir and fermentation conditions. Obtained results highlight the effectiveness of this multi-omics approach in identifying product-specific fungal communities and wine metabolite signatures, providing new tools that could be used to ensure wine authenticity and quality contro